Enhanced Automated Quantity Take-Off in Building Information Modeling Enhanced automated quantity take-off in building information modeling

Material quantity take-off is a necessary factor in estimating the cost of construction projects; accordingly, fast and precise estimations would better facilitate the overall construction process. In recent years, several Building Information Modeling (BIM) based applications (e.g., Autodesk Revit, Tekla Structure, Autodesk Navisworks Manage, and Solibri Model Checker) have emerged to assist in performing quantity take-off. Quantity take-off measurement using these applications is accurate when the elements length multiplies with their precise section area. Still, the process encounters errors when using element volumes or Industry Foundation Classes (IFC). In this study, the authors examined the embedded quantity take-off feature of these applications for sample steel and reinforced concrete structure and provided precautions in employing BIM properties. Consequently, an automated approach has been applied to facilitate an accurate quantity take-off by using an Application Program Interface (API) extracting information from a Navisworks model as well as database management systems. A case study is subsequently presented to demonstrate and validate the proposed methodology.